Protective case for electronic instruments



Dec. 9, 1969 D, M; B I 3,482,895

PROTECTIVE CASE FOR ELECTRONIC INSTRUMENTS Filed Jan. 26, 1968 INVENTOR.

DEV/W5 M EEC/(UN United States Patent US. Cl. 312-352 Claims ABSTRACT OF THE DISCLOSURE An instrument case for both transporting and containing electronic instruments which is both shock and .vibration resistent, embodies a protective outer shell and an inner instrument support carriage which is suspended in the outer shell by resilient shock-absorbing mounts.

The principal object of the disclosed invention is to provide a light, compact instrument case which may be used both as a transit and an operating case. The invented case provides a sturdy protective shell for instruments mounted in a shock and vibration resistant carriage. The case as designed permits installation of rack-mount, instrument units without modification, and permits operation of the units without their removal from the case. Special feet allow stacking of the cases during use, storage or transportation.

These and other features will become apparent from the full disclosure in the specification and accompanying drawings in which:

FIG. 1 is an exploded perspective view of the instrument case with two modules of an instrument unit;

, FIG. 2 is a front elevational view of the instrument case with the front cover removed;

FIG. 3 is a partial, enlarged section taken on the plane passing through the center of the elastomeric spacer indicated by the circular line 33 of FIG. 2;

FIG. 4 is a partial enlarged section of the outer shell Referring more specifically to the drawings and in particular to FIG. 1, the instrument case is formed with an outer shell 10, fabricated from pressure molded fiberglass. The outer shell is of substantially rectangular shape with rounded corners. The preferred embodiment has two opposing ends open to permit instruments that have rear power supplies or connection wiring to be operated while contained in the outer shell. However, for certain self-contained instruments, the outer shell may be fabricated with only one open end. Encompassing the edges of the outer shell 10 are seal flanges 12 and 14 fabricated from extruded aluminum. Two covers 16 and 18 are also fabricated from pressure molded fiberglass. Since the covers are constructed of molded fiberglass,

they may easily be provided with stacking ribs 20 which may be concave on the front cover 16 and convex on the rear cover 18 to permit the non-slip stacking of the instrument cases during storage or transit.

The edges of the covers 16 and 18 are encompassed, respectively, with seal flanges 22 and 24 fabricated from 3,482,895 Patented Dec. 9, 1969 extruded aluminum. The seal flange 22 on the front cover 16, as can be seen in FIG. 4, is formed with a male ridge which engages a mating groove in the female seal flange 12 .on the outer shell 10 when the front cover is placed on the outer shell. While not illustrated in detail, it is to be understood that the flanges 14 and 24 are constructed and cooperate similarly to the flanges 12 and 22. The covers 16 and 18 are secured in place by conventional metal latches 26 of which two are placed on the edge of each face of the covers..The latches 26 may be of a standard lever-clasp type and adapted to engage the inner edges of the flanges 12 and 14. One of the latches, and the manner in which it engages the inner edge of the flange 12, designated by 12, is shown in FIG. 4. If a resilient seal (not shown) is placed in the groove of the seal flanges 12 and 14 of the outer shell 10, the instrument case will be waterproof when the covers 16 and 18 are secured to the outer shell 10.

Since the outer shell 10 and covers 16 and 18 may be slightly out of square, it is desirable to maintain proper orientation of the covers with the outer shell to insure a proper joinder when'minor geometric imperfections are present. Therefore, in the present embodiment, the metal latches 26 at the top of the cover are spaced closer together than those at the bottom of the cover as illustrated in FIG. 2. Small button protrusions 28 are placed on the edge of the outer shell 10 such that if a cover 16 or 18 is out of phase, the metal latches 26 will be prevented from engaging the seal flanges 12 or 14 on the outer shell 10 by the button protrusions 28.

Two carrying handles 30 are attached to opposite sides of the outer shell 10 as illustrated in FIG. 1. The carrying handles 30 are spring loaded to lie flat against the face of the outer shell 10 when not in use.

The top and bottom faces of the shell 10 are designated, respectively, by the numerals 10' and 10". On the top face 10, as can be seen from FIG. 2, are four cylindrical studs 32 fixed to the outer shell near each of the corners. On the bottom face 10" are mounted four cylindrical collars 34. The collars 34 are mounted in alignment with the studs 32, as illustrated in FIG. 4, such that the instrument cases may be securely stacked in a horizontal position during use or transit. Preferably, the cylindrical collars 34 on the bottom face 10" of the outer shell are made of resilient material to provide the instrument cases with mounting feet suitable for placement on finished surfaces.

The instrument support carriage, designated by the numeral 36, is constructed of welded steel or aluminum members forming a box-like skeleton. The elevational members, designated by the numeral 38, are of essen* tially small box-beam construction. All other cross-members, designated by the numeral 40, are small L-beams which are welded to the elevational members 38 to form the instrument support carriage 36 illustra ed in FIG. 1.

Since many of the rack-mount instruments come in modules, it may become necessary to stack two or more instruments in one case. In the disclosed embodiment, the elevational members 38 have uniformly drilled and threaded holes 42 along the inner face for mounting adjustable slide rails 44 to carry the modules. The slide rails 44 can be fixed in the desired position by screws 46 at each end as illustrated in FIG. 3. The disclosure in FIG. 1 shows, as an example, an instrument unit comprising two modules 48a and 48b. The lower module 4811 is carried by cross-members 40 which comprise an integral part of the instrument support carriage 36. The upper module 48b is carried on the adjustable rails 44. The modules can be slid into the instrument case and, if desired, the modules can be secured to the instrument support carriage 36 by screwing or bolting the rack-mount tabs of the instruments, designated by the numeral 50, to the front 3 face of the elevational members 38 which are provided with threaded holes 52.

The instrument support carriage 36 is resiliently mounted to the outer shell by four elastomeric spacers 54. Although the support carriage 36 may be suspended by metallic spring mounts, it has been found that elastomeric spacers function most effectively in reduction of shock and vibration to the instruments. For ease in mounting, the elastomeric spacers 54 are cylindrical in shape with the central core removed as illustrated by the sectional view in FIG. 3. By changing the material used for the elastomeric spacers 54, the vibration and shock absorption characteristics of the mounting can be altered to suit the particular requirements of the instruments carried. For example, if unusually heavy instruments are carried, it would be preferable to mount them on less resilient spacers than are normally employed. Under the disclosed design, the spacers can be easily exchanged. Four studs 56 are attached to the inner wall of the outer shell 10 at predetermined positions. For strength, the studs 56 are welded or threaded into steel plates 58 which are attached to the outer shell 10 by bolts or rivets 60. The elastomeric spacers 54 are slipped over the studs 56 as illustrated in FIG. 3. The opposite ends of the elastomeric spacers are capped with steel caps 59. The center of each cap 59 is drilled and threaded for attachment to the elevational members 38. As the studs 56 are shorter than the length of the cylindrical elastomeric spacers 54, a screw 62 may be threaded through the end of the cap 59 without encountering the end of the stud 56. The studs 56 are arranged on the outer shell 10 such that the instrument support carriage 36 is suspended at points midway on the elevational members 38 as shown in FIG. 2. For assembly, the spacers 54 are first placed on the studs 56 and then capped. The support carriage 36 can then he slipped into the outer shell 10 and positioned for mounting. The support carriage 36 is then fastened in place by screws 62 which pass through the elevational members 38 and thread onto the steel caps 59 of the elastomeric spacers 54.

The support carriage 36 is suspended in the outer shell 10 with sufficient clearance around its periphery such that the support carriage 36 will not come in contact with the outer shell 10 during abusive transportational or operational handling of the instrument case when containing instruments. The positioning of the carriage in spaced relationship to the shell also provides for ventilation around an instrument supported on the carriage with the covers 16 and 18 removed. This is particularly advantageous where it is desired to operate an instrument while contained in the case.

The instrument case disclosed in the specification embodies the preferred design of my invention. It is apparent that the disclosed embodiment may be altered or modified in certain respects without departing from the spirit and scope of the invented concept of suspending an instrument package in a resiliently mounted support carriage.

I claim:

1. An instrument case comprising an outer shell of substantially rectangular shape having two opposite open ends, a seal flange fixed around the periphery of the edges at said open ends, two covers with short side faces said side faces having a seal flange fixed around the periphery of the edges of the faces which cooperate with the seal flange of the outer shell to provide a moisture proof seal, latching means for securing said covers to the outer shell, an instrument support carriage having structural frame members forming a box-like skeleton of dimension less than the internal dimensions of said outer shell, elastomeric spacers mounted at one end to said instrument support carriage, and mounted at the opposite end to the inner wall of said outer shell, parallel cross-rails adjustably mounted to the elevational members of said instrument support carriage for individual support of an instrument module inserted in one of said open ends of the instrument case.

2. The apparatus of claim 1 further characterized'by four mount units of a resilient material fixed near the corners on the bottom face of the outer shell, each with a central cylindrical portion removed, four cylindrical studs mounted near the corners on the top face of the outer shells opposite said bottom mount units so constructed that instrument cases may be stacked in modular fashion with the mount units of the upper case being resiliently seated on the cylindrical pins of the lower case.

3. The apparatus of claim 1 further characterized by at least two carrying handles which are spring loaded to lie flat against said outer shell when not in use.

4. A shock resistant instrument case comprising an outer shell of substantially rectangular shape having at least one open end, a cover for said open end, latching means for securing said cover to the outer shell, an instrument support carriage having structural frame members forming a rectangular box-like skelto-n of dimensions less than the internal dimensions of said outer shell, at least two parallel cross-rails adjustably mounted longitudinally on two sides of said support carriage, so co'nstructed that there is provided individual support of instrument modules inserted in said open end of the instrument case; said instrument support carriage being resiliently mounted to the inner walls of said outer shell by at least two spacers of size and resiliency sutficient to prevent said instrument support carriage from coming in contact with the outer shell during abusive transportational and operational handling of the instrument case when containing instruments.

5. A shock resistant instrument case, comprising:

(A) an outer shell of generally rectangular cross-section defining a receptacle having at least one open end;

(B) a removable cover adapted to be disposed over said open end to effect the closure thereof;

(C) latching means adapted to releasably secure said cover over said open end;

(D) a substantially rigid instrument carriage received within said shell, said carriage being adapted to releasably support an instrument;

(E) generally oppositely disposed resilient support means interposed between said carriage and the inner walls of said shell to suspend said carriage and an instrument supported thereby in spaced relationship to said inner walls for limited resilient movement relative thereto;

(F) support rail means mounted on opposite sides of said instrument carriage to provide individual support of instrument modules received in said open end of the instrument case; and,

(G) adjustment means to provide for adjustment of at least certain of said support rail means relative to said instrument carriage to accommodate instrument modules of different physical characteristics.

References Cited UNITED STATES PATENTS MARTHA L. RICE, Primary Examiner US. Cl. X.R. 6-46; 220-4. 7 

